Propylene can be an important feedstock for a variety of chemical processes. For example, propylene can be used in the production of polypropylene, propylene oxide, acrylonitrile, cumene, butyraldehyde, and acrylic acid. Propylene can be produced as a by-product of certain petrochemical processes, including the steam cracking, e.g., of ethane, liquefied petroleum gas (LPG), and/or naphtha and fluid catalytic cracking.
Certain methods for producing propylene are known in the art, including by olefins metathesis, methanol-to-olefins via syngas, high severity fluid catalytic cracking, and propane dehydrogenation. For example, propane dehydrogenation can be used to convert propane to propylene using a dehydrogenation catalyst. However, the dehydrogenation reaction can have side reactions, leading to catalyst deactivation.
Certain methods for regenerating dehydrogenation catalysts are known in the art. For example, U.S. Pat. No. 6,916,756 discloses a method of regenerating a dehydrogenation catalyst, including flushing the catalyst with an inert gas and passing an oxygen-containing gas mixture including an inert gas through the catalyst while increasing the oxygen concentration. U.S. Patent Publication No. 2014/0200385 discloses a process of regenerating a partially deactivated dehydrogenation catalyst. The method includes heating the catalyst to a temperature of at least 660° C., conditioning the heated catalyst in an oxygen-containing atmosphere and, optionally, stripping molecular oxygen from the conditioned catalyst.
However, there remains a need for improved techniques for the dehydrogenation of propane, including improved techniques for regenerating dehydrogenation catalysts.